Abstract

Gastrointestinal parasitism remains a major constraint in sheep production, and increasing anthelmintic resistance has stimulated interest in plant-based alternatives. This exploratory study evaluated the antiparasitic effect and preliminary biochemical safety of Chenopodium chilense Schrad., a plant species, in sheep from southern Chile. Thirty adult female Criollo Araucana sheep were allocated to five groups (n = 6): two groups received commercial anthelmintics, and three groups received oral C. chilense at 0.5, 1.0, or 2.0 g of "Paico powder" per kg of body weight. Fecal egg counts were monitored over a three-week follow-up period using the McMaster technique. Serum AST, GGT, ALP, total protein, albumin, total cholesterol, and triglycerides were evaluated before and after treatment in the C. chilense groups. Lower doses of C. chilense were associated with modest numerical reductions in fecal egg counts, whereas the highest dose showed greater variability and lower apparent efficacy. However, no statistically significant overall treatment effect was detected. In an exploratory analysis, parasite type was associated with variation in post-treatment egg counts. Biochemical analyses did not show a consistent dose-dependent pattern compatible with overt hepatotoxicity. These results suggest that C. chilense may have preliminary potential as a complementary phytotherapeutic candidate, but larger studies with improved sampling design, standardized phytochemical characterization, and greater statistical power are needed.